Stabilized stannous fluoride toothpaste

Abstract

Stannous fluoride containing toothpaste compositions including an alkyl vinyl ether and maleic anhydride or acid copolymer as a stabilizing agent for stannous fluoride and methods for preparing such stabilized compositions.

What is claimed is: 
     
       1. An aqueous toothpaste composition consisting essentially of water-unstable stannous fluoride and a lower alkyl vinyl ether and maleic anhydride copolymer as the essential stannous ion chelate forming stabilizer in an amount sufficient to effectively stabilize the stannous fluoride concentration against stannous oxide precipitation by providing oxidation protection to the stannous ion, the composition being substantially free from soluble pyrophosphates, silica containing compounds, and aldehyde group containing compounds. 
     
     
       2. A composition of claim 1 where the lower alkyl vinyl ether is methyl vinyl ether. 
     
     
       3. A composition of claim 1 where the amount of stannous fluoride included in the composition provides between about 0.05 to about 5.0 percent by weight stannous fluoride, the copolymer being present in an amount between about 0.5 to about 5.0 percent by weight, the weight ratio of stannous fluoride to copolymer being from between about 0.01 to about 1.0. 
     
     
       4. A composition of claim 1 where the composition includes an abrasive. 
     
     
       5. A composition of claim 4 where the abrasive is a calcium pyrophosphate.